1. Field of the Invention
The present invention relates to a card-like device including a portable card-like substrate and having display and audio functions, and a manufacturing method of same.
2. Description of the Related Art
In recent years, there has been commercialization of portable devices equipped with the function of displaying images captured from external devices. Such portable devices must also satisfy the demand for audio capability in addition to displaying images. The acoustic device installed in the portable device for this purpose is required not to spoil the portability of the portable device.
For example, Patent Publications 1, 2, and 3 disclose a structure in which a transparent panel member disposed in front of a display panel is caused to vibrate and resonate and using this effect to output sound. Patent Publication 3 discloses an acoustic device that takes advantage of resonance of the panel member. Specifically, the acoustic device disclosed in this publication relies on the action of bending wave of the panel member, and in this device, the resonance mode of the bending wave action and the distribution of acoustically important, related surface vibration of the panel member are adjusted to suit predetermined, or at least acceptable, acoustic device characteristics.
Applicant of the present invention has developed a technique for generating or picking up sound by causing the display panel to vibrate itself, and, in Patent Publication 4, discloses a card-type device including a portable card-like substrate of a structure integrating the display and audio functions and/or driving circuits therefor.    [Patent Publication 1]    Japanese Laid-Open Patent Publication No: 2000-152385 (published on May 30, 2000)    [Patent Publication 2]    National Publication of Translated Version, Tokuhyo Publication No. 2002-533957 (published on Oct. 8, 2002)    [Patent Publication 3]    National Publication of Translated Version, Tokuhyo Publication No. 2003-522426 (published on Jul. 22, 2003)    [Patent Publication 4]    Japanese Laid-Open Patent Publication No: 2003-244784 (published on Aug. 29, 2003)    [Patent Publication 5]    Japanese Laid-Open Patent Publication No: 2004-280071 (published on Oct. 7, 2004)    [Patent Publication 6]    Japanese Laid-Open Patent Publication No: 2812/1999 (published on Jan. 6, 1999)    [Patent Publication 7]    Japanese Laid-Open Patent Publication No: 194350/1999 (published on Jul. 21, 1999)    [Patent Publication 8]    Japanese Laid-Open Patent Publication No: 133761/2001 (published on May 18, 2001)